Fertiliser Spreading: Master Your Application Rate

Ensuring the correct amount of fertiliser is applied to your fields is crucial for optimal crop growth and minimising waste. Over-application can lead to environmental damage and increased costs, while under-application can result in reduced yields. This is where specialised tools like FertSpread come into play, offering a robust solution for farmers to calibrate their fertiliser spreading equipment with precision. FertSpread is an innovative on-line calculator and reporting tool designed to support on-farm calibration, accessible from any internet-connected device, be it a computer, tablet, or smartphone. By utilising field test results, FertSpread empowers you to calculate vital metrics such as your fertiliser product's Size Guide Number (SGN) and Uniformity Index (UI), guaranteeing that your application evenness falls within recommended ranges. Beyond these core calculations, it also determines fertiliser flow rate, the required spreader speed, and the actual application rate in kilograms per hectare (kg/ha). Ultimately, FertSpread's most significant contribution is its ability to analyse your broadcast spreader's configuration and, based on your test results, help you optimise your bout widths. This ensures you achieve consistent, cost-effective fertiliser spread patterns across your land, whenever possible.

Understanding the FertSpread Ecosystem

FertSpread operates in conjunction with the 'On-Farm Fertiliser Calibration Guidelines,' a vital resource for ensuring accurate data collection and analysis. It's important to note that different types of collection trays can influence the accuracy of captured data during testing. While experience suggests the uniformity calculations are reasonably accurate, the application rate might be slightly underreported. To verify your application rate, it's recommended to divide the quantity of fertiliser discharged by the area covered.

To leverage the full capabilities of FertSpread, including data saving for calculations and report generation, a login is required. The first-time user will need to register, which is a free process. This registration ensures that your specific farm data is securely stored, enabling personalised and accurate ongoing analysis.

Collecting Data for FertSpread: A Step-by-Step Guide

The accuracy of FertSpread's calculations is heavily reliant on the data being collected in a specific manner. Adhering to these protocols is essential to avoid errors. Printable Field Recording Sheets are available for download, formatted to ensure you capture all the necessary data for analysis. These sheets are designed to accommodate up to 41 collector trays: one in the centre and 20 on each side. Once you have collected your data using the Field Recording Sheet, log in to FertSpread and navigate to the 'Start Assessment' tab. Here, you can understand your current spreader configuration and run simulations by adjusting the bout widths to see the potential impact on your spreading patterns.

The Rate Calculator: Achieving Your Target Application

The 'Rate Calculator' is a specialised function within FertSpread designed to help you achieve your target application rate by calculating the necessary spreader travel speed. This tool is invaluable for ensuring that the correct amount of fertiliser is applied to each paddock. It's important to remember that this specific page, the Rate Calculator, does not save your data; it functions purely as a standalone calculator. Required information is indicated by yellow boxes, while calculated values are displayed in grey.

How to Use the Rate Calculator:

1. From the Home Page, click on the [RATE CALCULATOR] tab.
2. Enter the Target Application Rate (kg/ha) for your fertiliser.
3. Enter the proposed Spreader Bout Width (m centre to centre).
4. The tool will then calculate the amount of fertiliser discharged per metre of spreader travel.
5. Measure the actual amount of fertiliser being discharged over a specific time period.
6. Enter the amount of fertiliser caught in your collection trays.
7. Enter the time taken for this discharge.
8. The Spreader Discharge (Flow) Rate will be calculated.
9. The Target Travel Speed required to obtain your Target Application Rate will be calculated.
10. Measure your Actual Travel Speed on the ground.
11. Enter the Actual Travel Speed into the calculator.
12. The Actual Application Rate will be calculated.
13. Finally, the percentage of Actual to Target Application Rate will be displayed.

This allows you to make informed speed adjustments to correct any discrepancies and achieve your desired application rate. Fine-tuning your spreader's settings based on these calculations is key to efficient fertiliser management.

Fertiliser Spread Analysis: Understanding Uniformity

The 'Spread Analysis' feature of FertSpread leverages the data collected from your field tests to meticulously calculate the uniformity of application by broadcast spreaders. Fertiliser collected from catch trays across a single pass of the spreader is weighed, and this data is then entered into FertSpread. The system calculates both the Application Rate and the Coefficient of Variation (CV) for your current settings, as well as for alternative bout widths. This analysis can be performed for both 'round-and-round' and 'to-and-fro' application patterns, providing a comprehensive understanding of your spreader's performance.

Test Details and Vehicle Configuration:

To initiate a new analysis, click on the [START ASSESSMENT] tab, which will lead you to the 'Test Details' form. It is imperative that all yellow boxes, indicating required information, are filled in before you can proceed. If you are starting a new test, this form will be labelled 'Enter Test Details.' For existing tests, it will be labelled 'Edit Test Details.'

Within the 'Vehicle Details' section, the first step is to select a 'Test Type.' This selection customises the subsequent forms based on whether you are assessing a spreader, or a placement machine driven by either the PTO or a ground wheel. You will then need to fill in the remaining boxes, which will be incorporated into the final report that FertSpread generates. Crucially, the 'Travel Speed' must be accurately entered, as it is fundamental to all subsequent calculations.

Key Metrics Explained

Size Guide Number (SGN):

The SGN is a measure of the average diameter of fertiliser granules. It's important because granule size affects how fertiliser flows through the spreader and how it is distributed. Different SGNs require different spreader settings for optimal performance.

Uniformity Index (UI):

The UI quantifies how evenly the fertiliser is distributed across the spread width. A higher UI generally indicates a more uniform application, which is desirable for consistent crop nutrition.

Coefficient of Variation (CV):

The CV is a statistical measure of dispersion, often used in conjunction with uniformity analysis. It expresses the standard deviation as a percentage of the mean. A lower CV indicates greater uniformity in the fertiliser application.

Optimising Bout Widths

One of the most powerful features of FertSpread is its ability to simulate the effects of changing bout widths. The correct bout width is essential for achieving even coverage without overlaps or gaps. By entering your field test data, you can experiment with different bout widths within FertSpread to identify the setting that provides the best uniformity and application rate for your specific spreader and fertiliser product. This optimisation can lead to significant savings in fertiliser costs and improved crop performance.

Frequently Asked Questions (FAQs)

Q1: Is FertSpread free to use?
Yes, FertSpread is free to register and use. You only need an internet connection and a device.

Q2: Can I use FertSpread on my mobile phone?
Absolutely. FertSpread is designed to be accessible on any internet-connected device, including smartphones and tablets.

Q3: What data do I need to collect for a field test?
You will need to collect fertiliser caught in designated trays across the spread width after a single pass of the spreader. You also need to know the time taken for this collection and your actual travel speed.

Q4: How accurate is FertSpread?
FertSpread provides highly accurate calculations when data is collected according to the recommended protocols. While application rate might be slightly underreported with certain collection trays, uniformity calculations are generally very reliable.

Q5: What is the most important adjustment I can make using FertSpread?
Optimising your bout widths is often the most impactful adjustment you can make to improve the evenness and efficiency of your fertiliser application.

Conclusion

Mastering fertiliser application is no longer a guessing game. Tools like FertSpread provide the data-driven insights needed to calibrate your spreading equipment accurately, ensuring that your fertiliser is applied efficiently and effectively. By understanding and utilising the Rate Calculator and Spread Analysis features, you can optimise your operations, reduce waste, and contribute to both a healthier environment and a more profitable farming business. Remember to always consult the 'On-Farm Fertiliser Calibration Guidelines' and follow the data collection protocols diligently for the most reliable results. Accurate spreading is key to sustainable agriculture.